聊天室小程序
服务器端：
2.用户端连接后获取套接字的输入输出流，读取客户端发送过来的数据，然后发送到每一个连接到该服务器的客户端上
客户端：
1.实例化socket连接上对应的服务器
2.有信息发送时将数据写入，然后接受服务器端发送过来的数据
3.断开连接时，关闭数据输入输出流，关闭套接字
服务器端代码：
1 public class Server extends JFrame { 2 /** 3 * 4 */ 5 private static final long serialVersionUID = 1L; 6 private ServerSocket ss = null; 7 private boolean bStart = false; 8 9 private JTextArea taContent = new JTextArea(); 10 11 private int index = 0; //连接的客户端数量 12 13 List<Client> clients = new ArrayList<Client>(); //存放客户端对象 14 15 public void launchFrame() { //处理Frame 16 taContent.setEditable(false); //设置文本域不可编辑 17 18 taContent.setBackground(Color.DARK_GRAY); 19 taContent.setForeground(Color.YELLOW); 20 this.add(taContent); 21 this.setSize(300, 350); 22 this.setLocation(400, 200); 23 this.setTitle("TCP Server"); 24 this.setVisible(true); 25 this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 26 tcpMonitor(); 27 } 28 29 public void tcpMonitor() { 30 try { 31 ss = new ServerSocket(8888); //实例化serversocket等待客户端连接 32 bStart = true; 33 } catch (IOException e) { 34 35 e.printStackTrace(); 36 } 37 38 try { 39 while (bStart) { 40 index++; 41 Socket s = ss.accept(); 42 Client c = new Client(s); //实例化对象同时获取套接字的输入输出流 43 clients.add(c); 44 45 taContent.append(s.getInetAddress().getHostAddress() 46 + " connected " + index + " clients\n"); 47 new Thread(c).start(); 48 49 } 50 } catch (IOException e) { 51 e.printStackTrace(); 52 } finally { 53 try { 54 ss.close(); 55 } catch (IOException e) { 56 57 e.printStackTrace(); 58 } 59 } 60 61 } 62 63 public static void main(String args[]) { 64 Server ts = new Server(); 65 ts.launchFrame(); 66 } 67 68 private class Client implements Runnable { 69 DataInputStream dis = null; 70 DataOutputStream dos = null; 71 72 Socket s = null; 73 boolean bStart = false; 74 75 Client(Socket s) { 76 this.s = s; 77 try { 78 dis = new DataInputStream(s.getInputStream()); 79 dos = new DataOutputStream(s.getOutputStream()); 80 } catch (IOException e) { 81 e.printStackTrace(); 82 } 83 84 bStart = true; 85 } 86 87 public void sendToEveryClient(String str) { 88 try { 89 dos.writeUTF(str); 90 dos.flush(); 91 92 } catch (IOException e) { 93 index--; 94 clients.remove(this); 95 taContent.append(s.getInetAddress().getHostAddress() 96 + " exited " + index + " clients\n"); 97 System.out.println("对方退出了！我从List里面去掉了！"); 98 } 99 } 100 101 public void run() { 102 try { 103 while (bStart) { 104 String str = dis.readUTF(); 105 System.out.println(str); 106 for (int i = 0; i < clients.size(); i++) { 107 Client c = clients.get(i); 108 c.sendToEveryClient(str); 109 } 110 } 111 } catch (EOFException e) { 112 clients.remove(this); 113 taContent.append(s.getInetAddress().getHostAddress() 114 + " exited " + clients.size() + " clients\n"); 115 System.out.println("client closed"); 116 } catch (SocketException e) { 117 System.out.println("client closed"); 118 } catch (IOException e) { 119 e.printStackTrace(); 120 } finally { 121 try { 122 if (s != null) 123 s.close(); 124 if (dis != null) 125 dis.close(); 126 if (dos != null) 127 dos.close(); 128 } catch (IOException e) { 129 e.printStackTrace(); 130 } 131 } 132 } 133 134 } 135 136 } 客户端代码：
1 public class Client extends JFrame { 2 /** 3 * 4 */ 5 private static final long serialVersionUID = 1L; 6 TextArea taContent = new TextArea(); 7 JTextField tfTxt = new JTextField(20); 8 9 JButton send = new JButton("发送"); 10 JButton connect = new JButton("连接"); 11 JButton clear = new JButton("清空"); 12 13 boolean live = false; 14 JPanel p1 = new JPanel(); 15 JPanel p2 = new JPanel(); 16 17 Socket s = null; 18 DataOutputStream dos = null; 19 DataInputStream dis = null; 20 21 boolean bConnected = false; 22 23 Thread t = new Thread(new RecToServer()); //从服务器端接收数据 24 25 public void launchFrame() { 26 27 taContent.setEditable(false); 28 29 p2.setLayout(new FlowLayout(FlowLayout.CENTER, 10, 5)); 30 p2.add(send); 31 p2.add(connect); 32 p2.add(clear); 33 34 Container con = this.getContentPane(); 35 36 con.add(taContent, "North"); 37 con.add(tfTxt, "Center"); 38 con.add(p2, "South"); 39 40 this.setSize(300, 350); 41 this.setLocation(400, 200); 42 this.setTitle("Chat Client"); 43 44 this.setVisible(true); 45 this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 46 47 connect.addActionListener(new Connect()); 48 send.addActionListener(new SendMsg()); 49 clear.addActionListener(new ActionListener() { 50 public void actionPerformed(ActionEvent e) { 51 taContent.setText(""); 52 } 53 }); 54 } 55 56 public void connectToServer() { 57 try { 58 59 s = new Socket("127.0.0.1", 8888); 60 dos = new DataOutputStream(s.getOutputStream()); 61 dis = new DataInputStream(s.getInputStream()); 62 63 bConnected = true; 64 65 } catch (BindException e) { 66 System.out.println("找不到指定的服务器"); 67 } catch (UnknownHostException e) { 68 // TODO Auto-generated catch block 69 e.printStackTrace(); 70 } catch (IOException e) { 71 // TODO Auto-generated catch block 72 e.printStackTrace(); 73 } 74 75 } 76 77 public void disConnect() { 78 try { 79 if (s != null) { 80 s.close(); 81 } 82 83 if (dos != null) { 84 dos.close(); 85 } 86 if (dis != null) { 87 dis.close(); 88 } 89 } catch (IOException e) { 90 e.printStackTrace(); 91 } 92 } 93 94 public static void main(String args[]) { 95 Client tc = new Client(); 96 tc.launchFrame(); 97 } 98 99 private class Connect implements ActionListener { 100 public void actionPerformed(ActionEvent e) { 101 if (e.getActionCommand() == "连接") { 102 103 connectToServer(); 104 try { 105 t.start(); 106 } catch (IllegalThreadStateException ex) { 107 108 } 109 110 connect.setText("断开连接"); 111 112 } else if (e.getActionCommand() == "断开连接") { 113 disConnect(); 114 connect.setText("连接"); 115 } 116 117 } 118 } 119 120 private class SendMsg implements ActionListener { 121 public void actionPerformed(ActionEvent e) { 122 if (connect.getActionCommand() == "连接") { 123 JOptionPane.showMessageDialog(Client.this, 124 "没有找到指定的服务器", "错误提示", 1); 125 } else { 126 String str = tfTxt.getText(); 127 tfTxt.setText(""); 128 129 try { 130 dos.writeUTF(str); 131 dos.flush(); 132 } catch (SocketException ex) { 133 System.out.println("没有找到指定的服务器"); 134 JOptionPane.showMessageDialog(Client.this, 135 "没有找到指定的服务器", "错误提示", 1); 136 } catch (IOException ex) { 137 ex.printStackTrace(); 138 } 139 } 140 141 } 142 } 143 144 private class RecToServer implements Runnable { 145 public void run() { 146 try { 147 while (bConnected) { 148 String str = dis.readUTF(); 149 // System.out.println(str); 150 151 taContent.append(str + "\n"); 152 } 153 } catch (SocketException e) { 154 System.out.println("服务器已关闭"); 155 } catch (IOException e) { 156 e.printStackTrace(); 157 } 158 } 159 } 160 } 结果：
